Breast Cancer Home > Thioplex and Pregnancy
Women who are going to receive Thioplex (thiotepa) and are of childbearing age should use an effective form of birth control during treatment. This medication has been shown to cause miscarriages and birth defects during animal studies. As a pregnancy Category D medicine, Thioplex should only be given to a pregnant woman when the benefits outweigh the risks.
Thioplex® (thiotepa) is a prescription medication approved for the treatment of a variety of cancers. It is considered a pregnancy Category D medication, which means it may cause fetal harm if used during pregnancy.
The U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category D is a classification given to medicines that have been shown to present a risk to the fetus in studies of pregnant women but may still offer benefits that outweigh the risks the drug presents. A pregnancy Category D medicine may still be given to a pregnant woman if her healthcare provider believes that the benefits to the woman outweigh the possible risks to her unborn child.
In animal studies, Thioplex caused birth defects when given to pregnant mice and rats in doses that were equal to or less than the maximum recommended human dose. It also caused miscarriages when given to pregnant rabbits in doses that were approximately twice the maximum recommended human dose.
Thioplex has not been adequately studied in pregnant women. There is one report of a woman using the medication in the second and third trimester of pregnancy without causing harm to the fetus. It is important to note, however, that one report does not provide enough information to determine whether Thioplex can be safely used in pregnant women. In addition, there is no information on the use of the medicine in the first trimester, a critical period for fetal development.
Women of childbearing potential who receive Thioplex should use an effective form of birth control during treatment. If a man who receives this drug has a partner of childbearing potential, he or his partner should also use an effective form of birth control to avoid pregnancy.
It should be noted that Thioplex may interfere with a women's normal menstrual cycle. You may have irregular periods, or stop menstruating altogether during treatment. Do not assume, however, that you cannot get pregnant. You may still need to use birth control, even if you stop having a monthly period while using this medication. Talk to your healthcare provider about possible birth control options for your particular situation.